introduced StringIO

introduce line oriented communication
+ HasIodev Mixin
+ minor fixes
Change-Id: I22605824d2f45147224840172bae281f85c80a11
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/21953
Tested-by: JenkinsCodeReview <bjoern_pedersen@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>

secop/errors.py

@@ -98,6 +98,14 @@ class CommunicationFailedError(SECoPError):
     pass
 
 
+class SilentError(SECoPError):
+    pass
+
+
+class CommunicationSilentError(SilentError, CommunicationFailedError):
+    name = 'CommunicationFailed'
+
+
 class IsBusyError(SECoPError):
     pass